Fleurus (French pronunciation: [flœ.ʁys] ⓘ; Walloon: Fleuru) is a city and municipality of Wallonia located in the province of Hainaut, Belgium.

The municipality consists of the following districts: Brye, Heppignies, Fleurus, Lambusart, Saint-Amand, Wagnelée, Wanfercée-Baulet (wa: Wanfercêye-Bålet), and Wangenies.

Traces of agriculture dating back to the Neolithic Age were found in area known as Fleurjoux and Neuve Baraque.

Later the site saw the construction of the Chaussée Brunehaut, a road network of uncertain origin, perhaps attributable to the Roman Empire.

In World War II, the only fighting near Fleurus was a tank battle southwest of the town at Vieux Campinaire in September 1944.